This invention relates to a method and system that uses a taper-lock laser weld joint for air induction components.
Air induction systems typically include several different induction components, such as air cleaners, air hoses, resonators, intake manifolds, etc., with each component being attached to at least one other component to provide an air induction assembly forming a pathway for air moving through the air induction system. Various different attachment methods can be used to attach plastic air induction components to each other or to weld portions of such components together. One preferred method utilizes vibration welding to permanently weld portions of components together.
In a traditional vibration welding process, each section of the air induction component includes a flange against which a clamping force is exerted to clamp the sections of the component together prior to welding. Once the sections of the component are clamped together, one section is vibrated against the other along a predetermined weld bead to melt the plastic and attach the components together.
The traditional vibration welding method has some disadvantages. For example, additional component material is required to form the flanges, beads and flash traps on the components. This material adds extra weight and cost and provides no additional benefit to the components, once the air induction system is assembled on to an engine. Further, exerting and maintaining the clamping force during the vibration welding process also adds cost.
Because vibration welding removes material as flash during the melting process, the weld beads must be designed with the additional material added. Since the amount of material removed from any section of weld bead at an angle to the clamping force depends upon the angle, calculation of the correct amount of material to add can be complicated. Another disadvantage of vibration welding is that the weld bead must be mounted on a flange which displaces the joint laterally from a true tensile load. Such a joint is subjected to a peel component, which considerably weakens the joint.
Another joining process for plastic air induction components is through-transmission laser welding. This process requires the two surfaces that are to be joined together, be clamped together with the clamp components. If these two surfaces are simply overlapping flat surfaces, the two clamp components must be located directly on the surface to be welded, one above and one below. In this configuration, the laser must either pass through one of the clamps or the clamp must move away just before the traveling laser approaches, then the clamp must re-engage after the laser passes. In this latter example the opening, moving away, moving back into place, and then closing of the clamp significantly slows the laser welding process down. In the former case, one part of the clamp must be formed from a transparent material so that the laser beam can pass through the clamp. Using a transparent material for the clamp is not desirable because if the clamp material becomes dirty, the energy of the laser beam is absorbed and can cause the clamp to heat up and melt or shatter. Hence neither one of these solutions is satisfactory.
Thus, it is desirable to have a laser beam welding method and apparatus that can provide a clear laser path to the surface to be welded (faying surface) of the component, as well as overcoming the other above mentioned deficiencies with the prior art. Further, the process should use less material and require no change in the geometry of the component during welding such that the welds resulting are much stronger because the welds are formed to fail in tension rather than having a peel component.